[Pleomorphic adenoma of the parotid gland, rules for resection]

The importance of complete excision of a benign pleomorphic adenoma is illustrated by two patients' histories. A 28-year-old man underwent a local excision of a nodule under the left ear without histological confirmation. Ten years later he returned to our institute with a large multilocular process and subcutaneous nodules. Cytology showed pleomorphic adenoma. Patient was treated with total facial nerve preserving parotidectomy and radiotherapy. An 81-year-old male underwent a surgical removal of a swelling under his left ear eight years before admission for a large diffusely infiltrating tumor in the neck. Repeated cytology showed carcinoma ex pleomorphic adenoma. This tumor was inoperable and he was treated by palliative irradiation. In case of incomplete resection, pleomorphic adenoma cells are spilled with an increasing chance of local recurrence. Also degeneration into carcinoma ex pleomorphic adenoma is possible after incomplete resection, with impact on survival. These risks of residual disease determine the need of centralization of diagnosis and treatment of this benign parotid tumor.